Method of and device for operating appliances having driven masses

ABSTRACT

A device for the cyclic acceleration and deceleration or braking of a mass over a short period of time. A mechanical or pneumatic spring is used to store during deceleration or braking the kinetic energy of the mass as it is slowed down. The stored or potential energy in the spring is then applied to the mass during acceleration. Two two-armed levers are coupled to the springs for transmitting energy between the mass and the spring. Locks or swivel pawls are used to couple and de-couple the mass to the levers such that the levers are moved in a manner to transfer the kinetic energy of the mass to the spring during the deceleration and to transfer the potential energy of the spring to the mass during acceleration.

United States Patent [191 Nauen METHOD OF AND DEVICE FOR OPERATING APPLIANCES HAVING DRIVEN MASSES [76] Inventor: Karl-Heinz Nauen, Silberbergerstr.

20, Bremen, Germany [22] Filed: Sept. 25, 1970 [21] Appl. No.: 75,512

[30] Foreign Application Priority Data Sept. 26, 1969 Germany ..P 19 48 683.3

[52] US. Cl... ..l85/39, 185/41, 60/7 R [51] Int. Cl ..F03g 1/00 [58] Field of Search ..l85/l0, 11, 126, I 185/41, 6, 39; 60]? AB, 7 R; 92/8, 143; 91/5 [56] References Cited UNITED STATES PATENTS 236,936 1/1881 1 Dawson 507,033 10/1893 De Normanville 2,636,340 4/1953 Llamozas 3,023,738 3/1962 Burgess ..91/471 X [4 1 Apr. 17, 1973 3,266,233 8/1966 Farrall ..60/7 R FOREIGN PATENTS OR APPLICATIONS 729,941 5/1955 Great Britain ..60/$2 HF Primary Examiner-Edgar W. Geoghegan Attorney-Sughrue, Rothwell, Mion, Zinn & Macpeak [5 7] ABSTRACT A device for the cyclic acceleration and deceleration or braking of a mass over a short period of time. A mechanical or pneumatic spring is used to store during deceleration or braking the kinetic energy of the mass as it is slowed down. The storedor potential energy in the spring is then applied to the mass during acceleration. Two two-armed levers are coupled to the springsfor transmitting energy between the mass and the spring. Locks or swivel pawls are used to couple and de-couple the mass to the levers such that the levers are moved in a manner to transfer the kinetic energy of the mass to the spring during the deceleration and to transfer the potential energy of the spring to the mass during acceleration.

8 Claims, 6 Drawing Figures PATENTEDAPR] 71973 SHEET 1 [IF 3 PATENTEB APR 1 7 I973- SHEET 2 OF 3 PATENTEB APR 1 H875 SHEET 3 UF 3 METHOD OF AND DEVICE FOR OPERATING APPLIANCES HAVING DRIVEN MASSES This invention relates to a method of and a device for operating appliances having driven masses which are accelerated and decelerated over short periods of time.

In almost all fields of technology it is often necessary to accelerate large masses to relatively high speeds within a short period of time and then to bring them to a standstill. This problem arises, for example, in devices incorporating rotating parts, e.g., turntables and the like, which are driven in cyclic rotational movements. Practical experience has shown that the control of large masses is very difficult when they are to be accelerated and decelerated at high speed.

It is the object of the invention to provide means by which the operation of such appliances is facilitated and higher speeds can be reached or speed decreased even with larger masses more quickly than with appliances hitherto commonly known.

To attain this the present invention provides a method of operating appliances having driven masses, and more specifically masses which are accelerated and decelerated over short periods of time, characterized in that the kinetic energy of a mass is stored as a potential energy when the mass is slowed and released again as a kinetic energy by which the mass is driven at the beginning of an acceleration process.

By storing and releasing the energy, the delay, that is i the deceleration of the mass from a high speed to bring it to a standstill is facilitated particularly when springs are used to store the energy. Further it is possible to accelerate the mass at the beginning of a new motion cycle by means of the kinetic energy at the moment of its release, with the result that even with large masses the desired high speed is reached within a very short time.

The invention can be applied advantageously, for example, with a novel device for removing packages, conveyed at high speed, in particular banana-boxes travelling on a conveyor band which are subsequently transferred to another conveyor belt extending at right angles to the conveyor band. In this process, the mass, i.e., the banana-boxes, move through a quarter circle at high speed. Because the banana-boxes are travelling at high speed, the rhythmically rotating transfer device must be accelerated to a high speed for a short time and then slowed down to a standstill.

According to the invention, a device having machine parts which are accelerated and decelerated in cycles and which are provided with means for carrying out the method is characterized in that when the moving machine part is decelerated it tensions, such as compressing a spring which works as an energy accumulator. The force of said spring has an accelerating effect on the machine part at the commencement of a new movement cycle.

Preferred embodiments of the invention will now be described by way of example and with reference to the accompanying drawings, in which:

FIG. 1 is a schematic plan view of a device in which the invention can be applied advantageously.

FIGS. 2 to 4 show a method of constructing an energy accumulator in accordance with the invention in different working phases, and

FIGS. 5 and 6 show another method of constructing an energy accumulator, in different working phases.

The invention can be applied wherever large masses, e.g., machine parts or useful loads, are to be moved in cycles with relative high speed. FIG. 1 shows as an ex-' ample a device in which cardboard banana boxes 10 are to be conveyed at high speed on a distributor band 11 to a discharge belt 12 which extends at right angles to the distributor band 11. The banana boxes 10 are engaged by a turning device, i.e., by on of four supporting arms 13 of a spider 14 having suitable holding means. The banana boxes are moved along a course of about a quarter-circle and set down on the discharge belt 12. Consequently, the moved machine part, that is the spider 14, is at a standstill at the moment when a banana box 10 is engaged or disengaged. Since the banana boxes 10 are travelling at high speed when they approach the respective arm 13, the spider 14 must have a high turning speed.

The invention now proposes to provide an energy accumulator 15 for storing the kinetic energy produced during the slowing down, i.e., the deceleration of the moved machine part (spider 14), until the spider 14' is in a stop position. With the beginning of the following movement cycle, the energy accumulator 15 returns the accumulated energy to the spider 14 in an accelerating sense.

In the given embodiments shown and described the energy accumulator uses springs, namely pneumatic springs, as shown in FIGS. 2 to 4, and mechanical springs, as shown in FIGS. 5 and 6.

In FIGS. 2 to 6, a supporting arm 13 in cross section is shown as a movable mass M to simplify the disclosure. This mass M is thought to be moved in the direction of the arrows 16 along a straight or a curved path from the left to the right in these FIGURES.

The mass M is decelerated by means of the energy accumulator 15 in that said mass M mounts the energy accumulator l5 and in doing so produces tension in the latter. In the embodiment shown in FIGS. 2 to 4 the mass M is provided with locks 17 and 18 which actuate the energy accumulator 15 or absorb its motion power. Locks 17 and 18 are each arranged for unilateral action. The energy accumulator comprises in this embodiment two pivotally mounted two-armed levers l9 and 20 which are connected to each other by toothed segments 21 and 22 in such a way that any movement of one lever is transferred to the other.

A pneumatic spring in the form of an air cylinder 23 is provided for storing the energy. The interior of this air cylinder 23 is divided by a piston 24 into two chambers 25 and 26. The air cylinder 23 is connected to the lever 20, whereas the piston 24 is connected via a piston rod 27 to the other lever 19. The two-armed levers l9 and 20 are each composed of a long arin 19a and 20a respectively and a shorter arm 19b and 20b respectively. The air cylinder 23 is arranged intentionally between the long arms 19a and 20a of the twoarmed levers l9 and 20, whereas the shorter arms 1% and 20b serve to receive and transmit the energy. A compression spring 28 is disposed between the upper ends of the shorter arms 1% and 20b an serves the purpose of keeping both two-armed levers 19 and 20 in their initial positions when the air cylinder 23 is released.

When receiving and storing energy the piston 24 in the air cylinder 23 is moved from its initial position shown in FIG. 2 into the position shown in FIG. 3 and in doing so compresses the air in the chamber 26. When this energy is being transmitted, the piston 24 is returned into its initial position shown in FIG. 2. FIG. 4 shows the instant of energy transmission.

The chambers 25 and 26 are connected to each other by a compensation line 29 which incorporates a valve 30. This valve 30 is so controlled that the chambers 25 and 26 are connected to each other in the initial position of the piston 24 (FIG. 2) in which no energy is stored. An exchange of air can thus take place which prevents high temperatures from arising when short working cycles occur in rapid succession. The valve 30 is controlled in such a way that a compensation of air between the chambers 25 and 26 takes place immediately before a movement cycle is finished (FIG.

The locks 17 and 18 which are provided on the mass M and which are effective as unilateral pawls by means .of flat iron bars 31 and 32, can be moved up and down along the mass M, tensioning springs 45 loading the locks 17 and 18 in the direction towards their lower end positions.

When the mass M arrives at one of the supporting arms 13 of the spider 14, the lock 17 is raised and thus allowed to move past the first lever 20 as well as past the second lever 19 until said lock 17 arrives in the position shown in FIG. 3. The other lock 18 cannot move past the lever 20, but causes this lever 20 to move in a horizontal swing from the position shown in FIG. 2 into the position shown in FIG. 3. Since the levers l9 and 20 are operatively connected with each other by the toothed segments 21 and 22, the second lever 19 carries out a similar straddling movement, so that a corresponding tension in the air cylinder 23 is produced.

To enable the release of energy, a corresponding actuation device is provided which consists of a doublearmed swinging lever 33, to one end of which an electric magnet 34 is attached. The swinging lever 33 is installed in such a way that its actuating end 35 can engage under a pin 36 provided on the lock 18. When the swinging lever 33 is tilted after the electric magnet 34 (FIG. 4) has been actuated, the lock 18 is lifted thus releasing the levers 19 and 20. Since the second lock' 17 remains in the locking position, the energy which is now delivered is transferred to the mass M in the desired motional direction of motion.

In the embodiment of the energy accumulator 15 shown in FIGS. and 6 a tension spring 37 is placed between the long arms 19a and 20a of the levers 19 and 20. Two swivelling pawls 38 and 39 are provided as locks for the mass M, and are fixed in locking position (accumulation of energy) according to FIG. 5 by electric magnets 40 and 41. The electric magnets 40 and 41 activate axially adjustable pins, each of which engage return springs 44 after carr ing out a swivelling motion. The way in which this evrce operates is t at when the mass M arrives, that is when it is slowed down, the swivelling pawl 38 is locked by the electric magnet 41 whereas the swivelling pawl 39 can be pivoted. The mass thus strikes the nose 43 of the swivelling pawl 38, and in doing so activates the levers 19 and 20. Energy is released (FIG. 6) when the lock is set free by the swivelling pawl 38, when the swivelling pawl 39 is fixed so that the energy can now be transferred to the mass M in the direction of movement.

What is claimed is:

1. A device for the cyclic acceleration and deceleration or braking in the same direction of masses over short periods of time comprising spring means for storing, during deceleration or barking, in a first direction, the kinetic energy of the mass as potential energy and for releasing said energy to said mass during acceleration in the same direction; lever means, coupled to said spring means, for transmitting energy between said mass and said spring means; engaging means, coupling said mass to said lever means, for moving said lever means in a manner to transfer the kinetic energy of the mass to the spring means during deceleration and to transfer the potential energy of the spring means to the mass during acceleration.

2. A device according to claim 1, wherein energy is introduced into said spring means by said mass acting on a first part of said lever means and transmitted from the spring means to the mass by said spring means acting on a second part of said lever means.

3. A device according to claim 2, wherein said lever means comprises two two-armed levers, each lever having a toothed member attached thereto wherein said levers are operatively connected by said toothed members.

4. A device according to claim 1, further including electromagnets for operating said engaging means.

5. The device according to claim 1, wherein said engaging means is a lock means. 1

6. The device according to claim 1, wherein said engaging means is a swivel pawl means.

'7. The device according to claim 1, wherein said spring means is a pneumatic spring.

8. The device according to claim 1, wherein said spring means is a mechanical spring. 

1. A device for the cyclic aCceleration and deceleration or braking in the same direction of masses over short periods of time comprising spring means for storing, during deceleration or braking, in a first direction, the kinetic energy of the mass as potential energy and for releasing said energy to said mass during acceleration in the same direction; lever means, coupled to said spring means, for transmitting energy between said mass and said spring means; engaging means, coupling said mass to said lever means, for moving said lever means in a manner to transfer the kinetic energy of the mass to the spring means during deceleration and to transfer the potential energy of the spring means to the mass during acceleration.
 2. A device according to claim 1, wherein energy is introduced into said spring means by said mass acting on a first part of said lever means and transmitted from the spring means to the mass by said spring means acting on a second part of said lever means.
 3. A device according to claim 2, wherein said lever means comprises two two-armed levers, each lever having a toothed member attached thereto wherein said levers are operatively connected by said toothed members.
 4. A device according to claim 1, further including electromagnets for operating said engaging means.
 5. The device according to claim 1, wherein said engaging means is a lock means.
 6. The device according to claim 1, wherein said engaging means is a swivel pawl means.
 7. The device according to claim 1, wherein said spring means is a pneumatic spring.
 8. The device according to claim 1, wherein said spring means is a mechanical spring. 